Before a rusty old bridge in Cincinnati, Ohio, Thursday, President Obama threw a political punch at his foes. “Mr. Boehner, Mr. McConnell, help us rebuild this bridge. Help us rebuild America,” the President said, just up river from the Brent Spence Bridge. The crowd before him, a couple hundred strong with union t-shirts and the periodic cries of “You tell them, Mr. President,” cheered with delight, chanting “Pass the bill, pass the bill,” as Obama looked out victoriously beyond the television cameras.

Neither Ohio Rep. John Boehner nor Kentucky Sen. Mitch McConnell were present to hear the appeal from their President, though they had been invited to the speech staged on the banks of a river that divides their two states. But that wasn’t the point.

This event was all theatrics and good photo ops. Obama wasn’t really saying, “What on earth are you waiting for?” when he asked Congress “What on earth are you waiting for?” (His spokesman on the flight over had said the President understood that Congress was engaged in other matters of “urgent need” at the moment.) The bridge behind him wasn’t really going to be fixed right away if his bill passed. (It won’t be replaced before 2013, no matter what bills pass Congress.) Republican leaders don’t even oppose replacing the bridge.

What mattered was that Obama was calling out his political opponents by name, and demanding that they pass his $450 billion stimulus bill, the American Jobs Act, that he proposed 10 days ago. What mattered was that Obama was going on offense.

The message, to both independent voters and the Democratic base, was unmistakable: This wasn’t the Obama of June, who appeared at shiny new factories to show off newfangled technology, trying to create enthusiasm for an economic recovery that few Americans were feeling. This was a new Obama, standing in front of a bridge declared “functionally obsolete,” and demanding that his political foes get out of the way of the nation’s future.

This last part is, perhaps, the biggest shift in the White House strategy this fall. Ever since Obama passed the 2009 stimulus bill in his second month in office, he has toured the country looking to highlight the bright spots of a mostly dismal situation. He found the new manufacturing plants, the reopened car factories, the solar panel arrays, and he spoke optimistically of the country’s future. It was a message that made sense politically—Obama owned both the stimulus bill and the weak economic recovery—but struck discordant notes. For a country still suffering economic anxiety and job loss, a new car battery technology offered little solace.

Now, in the wake of renewed recession fears and a disastrous summer, Obama has decided to swap his good news photo ops for bad news photo ops. The Brent Spence Bridge is, after all, a sign of what is wrong with the country, not what is right with it: a double-decker mess of too few lanes with visible corrosion on its underbelly.

The President has decided, for the moment at least, not to campaign across the country on his own accomplishments, but on his new aspirations to improve the lives of the country’s voters. In the new populist frame, Obama is not selling the past or the present, he is fighting for a different future, against ideological extremists, economic opportunists and selfish millionaires and billionaires.

“The Republicans in Congress call this class warfare,” Obama said, later in the speech, discussing the opposition to his proposals for to pay for his jobs bill. “Well you know what? If asking a billionaire to pay the same tax rate as plumber or teacher makes me a warrior for the middle class, I’ll wear that charge as a badge of honor. Because the only class warfare I’ve seen is the battle that’s been waged against the middle class in this country for a decade.” The hand-picked crowd—no more open-seating town halls—ate this up, wild with cheers and applause.

The question for Obama is whether his pivot has come too late. A significant portion of the country long ago tuned the President out. Though his jobs plan has proved more popular than not, it fails to break 50% support in the polls. His own approval rating for handling the economy now stands at about 36%, down from 41% in September of 2010 and 51% in September of 2009.

Republicans, meanwhile, are throwing punches of their own. “President Obama may think the best way to distract people from the challenges we face is to stand near a bridge in a swing state and pit one group of Americans against another, and hope his critics look bad if they don’t go along with him,” McConnell said on Wednesday. “But I don’t think he’s fooling anyone.”

McConnell’s comments, directly attacking the credibility of the commander-in-chief, show no change in tone. He has been doing this for quite a while. But now McConnell has an opponent in Obama who is calling him out as well, by name, on his home turf. These are the new terms, and it’s a fight that is set to continue until election day 2012, at least.